This paper presents application of split ring resonators (SRR) in conventional waveguide slot array antenna to achieve performance improvement and multiband characteristics. Three SRRs have been placed on the transverse plane of a conventional slotted waveguide and has been simulated and measured. The measured results show that the antenna has dual band response with respective 10 dB return loss bandwidth 8.23–9.23 GHz (11.45%) and 9.68–11.01 GHz (12.87%). The measured gain and radiation pattern reveal that the proposed antenna has higher gain and front to back radiation ratio as compared with a conventional slotted waveguide antenna. Equivalent circuit of the proposed antenna also has been presented.